[Pan-users] Re: Problem with filtering

[Duncan]

Torstein Sunde posted
<address@hidden>, excerpted below,
 on Sat, 20 Sep 2003 19:31:40 +0200:

> Edith Gross wrote:
> 
>> When I try to find the headers in a newsgroup (a.b.s.m.classical) that
>> 
>> contain the word 'Richter' nothing happens (though I get the message
>> 'filtering...'. When I look for the word 'Beethoven' I get the right
>> resul immediately.
> 
> I've seen similar behaviour when trying Pan 0.14.2 on a computer with
> Windows 2000.  I haven't seen it on Linux.
> 
> On Windows, I think the problem became less frequent (from always/almost
> always to often/sometimes) after upgrading GTK+ from 2.2.3 to 2.2.4.

I was thinking it might be a charset issue.  W2K supports the theory,
since it runs unichar I believe.  Do the filter failures possibly have
accents or umlauts or some such thing in some languages, but possibly not
as displayed in the font being used?  I'm guessing it might not be
matching because it literally doesn't match, since they are different
characters based on character-set.

> Last time (with GTK+ 2.2.4) I also observed another app (a compiler)
> freezing while Pan was stuck filtering.  When I terminated Pan, the other
> app was running again.

This looks like a resource contention issue.  Some sort of thing where
application A is using X but can't continue until it gets Y, but
application B has Y and can't continue until it gets X, with both X and Y
being single use objects or non-reentrant code, meaning a deadlock
situation.  NT and successors are /supposed/ to be designed as fully
reentrant, and with individual apps each getting their own exclusive copy
of "single use" items, but as we all know, theory and practice aren't
always the same, except in theory.  <g>

If that's indeed what it is, presumably in code having to do with
charset conversion based on the above, killing the one app would free the
resource needed by the other app, so it could continue normally.

You don't mention what compiler it was or what it was compiling, but it's
possible both PAN (or rather more likely the GTK language library
functions) and the compiler were contending for the same code segment,
altho MS apps say wouldn't because they don't generally use said code
segment, which is there for "legacy and compatibility" reasons, but not
something they regularly use. (Or, it might be used in devel, but not
commonly otherwise, and they figure its not likely you'd be trying to
compile multiple apps at the same time..)

In this scenario, the old GTK version may have not used it correctly, so
caused issues due to that, while the new one makes better use of it so
doesn't malfunction as often, but does tie down the resources now causing
the occasional conflict with anything else that happens to try to use the
resources in reverse order when they both happen to try to access the same
shared library/system code at the same time.

That's a lot of supposition, I will admit, but it's plausible..

-- 
Duncan - List replies preferred.   No HTML msgs.
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